Purity classess

The class of cleanliness of a premise is precisely regulated requirements on a level of various sort of impurity and particles in the air. Classes of purity are differing in number of particles of a certain size per unit volume. This parameter is one of the most important in the classification of cleanrooms.

GOST R 52249-2009 “Rules for the production and quality control of medicinal products”

Classes characterize the degree of cleanliness of air in a clean room. Classification of clean rooms has a number of distinctive features, with respect to those industries in which they are used.

Some applications:

Class 1 (ISO3)

Production of integrated microcircuits.

Class 10 (ISO4)

The production of integrated microcircuits with a conductor spacing of less than 2 μm.

Class 100 (ISO5)

Aseptic production of injections requiring the absence of microorganisms and particles. Surgery for implantation or transplantation. Isolation of patients with immune deficiency, including after bone marrow transplantation.

Class 1000 (ISO6)

Production of high-level optical elements. Assembly and testing of precision gyroscopes. Assembly of miniature bearings.

Local area for operations, representing a high risk for product quality (filling and capping areas).

Class B

The zone directly surrounding zone A and intended for the preparation of solutions.

Class C and D

Zones, for performing less important stages of production of sterile products. Work with components after washing.

A clean room is a technically complex, expensive and responsible engineering structure. To ensure a given class of purity, an integrated approach is required. For its implementation, it is required to follow the basic principles of ensuring cleanliness at all stages of creating a clean room, which include:

Development of the concept of declared cleanliness class;

Design;

Building;

Certification;

Operation;

Conditionally, it is possible to single out the following basic approaches to the creation of clean rooms:

Determination of the principle of separation of zones with different classes of purity. Development of planning solutions for clean rooms.

Formation of air flows. Provide the necessary characteristics of unidirectional air flow.

Ensuring the balance of air exchange, the necessary proportion of outdoor air, and for rooms of classes ISO 5 – ISO 9 – the frequency of air exchange.

Application of HEPA and ULPA filters and multistage air filtration.

Ensuring the necessary pressure drop.

Development of effective design and construction solutions, use of proper materials and equipment.

Monitoring of air parameters: concentration of particles, concentration of microorganisms (if necessary), velocity of unidirectional air flow, pressure drop, integrity of HEPA and ULPA filters, recovery time of clean room parameters and so on.

Proper use of clean rooms, including requirements for clothing, cleaning procedures, disinfection, etc.